I would have thought theses commands would be fun to play with but they only seem to effect vehicles on land or in the sea.
They don't seem to be working on falling vehicles, if you weight the engine it should drop engine first but we get that horrible flat fall and it lands on all four wheels.
Adding mass to a chopper in flight did seem to have some effect of making the controls sluggish but no effect on lift.
It just seems odd you add weight on the ground and the truck will stand on it's nose but in the air nothing.